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I finally got the big engine in the car so I guess i should stick a fork in it! I'll probably never paint it, I like the rat rod aesthetic too much. I started the build back in '05 when I bought an orphaned CMC Miata chassis and box of parts from Jack/Kinetic Vehicles. After a bad motorcycle accident, new house, some serious medical issues and almost 10 years it's mostly done.modified CMC Miata chassisMiata uprights and brakesMy own rear control armsJacks front upper control armsGaz shocksMiata 6 sp transcustom adapter for NB miata trans to Duratec engineheavily modded Duratec 2.3 enginefancy wheels and tiresMy sporadic build log is herehttp://www.lightningbugcars.com/locost.html

I hate to rain on your parade, but since you posted up the dyno numbers...

I was very happy with my dyno results, which were run on the same type of dyno. I've since had it run on an inertial drum-in-floor type, which is far more common. So much more common that the results from the drum-type are used for comparison purposes. Unfortunately, I found that Dynopack dynos read ~20% higher than the drum type. Granted, dynos are properly used for tuning, so absolute numbers don't matter. However, it still was very humbling to find that my "400whp" car was more like 320 hp on any other dyno. Amazing in this day of six digits past the decimal, dynos can agree better than 20%!

Don't worry you're not raining on my parade, it's already been rained on, I was very underwhelmed by the dyno #s. Looking at some of the Ford Focus specific sites and the hp #s posted there for engine builds very similar to mine, the #s I posted seem quite low. When I was building the engine I had a target goal of 220hp based on some builds that were almost identical to mine except they were running lower compression, a stock manifold, but the identical cam...they were posting 220whp from a Dynojet!? I think the #s were legit, the guy was a gifted tuner.

I was happy to believe the numbers I was handed, until I gave a friend a ride who observed, "with the power you're claiming, I expect to see tire smoke in third gear" and that wasn't happening. It wasn't until I researched the issue did it become clear how "optimistic" Dynopack dynos are.

That said, there's always turbocharging if you need more It's either that or if you stay normally aspirated, the only way to more power is more revs and higher compression. The trouble there is that places like Laguna have seriously tight sound limits.

I'm running 12.5:1 comp ratio (not much room to go higher and still be streetable on pump gas), ported head w/+1mm valves, suzuki gsxr 1000 itbs (probably on the small side for this engine), Crane stg3 cams (not too big might go bigger), and big headers. I put a Supertrapp on the end of my pipe because I was at Laguna and I was also going deaf I actually brought up the Dynapack 20% difference with the shop yesterday and this was their response

Quote:

With regards to different dyno's, there's a common misconception that Dynapack's read higher. This came about because of one SoCal dyno which was calibrated to measure flywheel hp/tq. I've personally used this particular dyno and compared it with mine using the same test vehicle. That one reads 18-20% higher. Since then ~2005, Dynapack has changed their software as well as their calibration on all their dynos to read actual hp/tq measured at the hub. The SoCal shop chose not to change their calibration. That said, in testing with other local bay area Dynojets, Mustang, Dyno Dynamics dynos, our dyno's variance is +0/-5% in comparison.

Even with the Dynapack rading correctly and a reputable (good but not gifted) tuner, I agree those numbers definitely seem low for that engine. Was the Supertrapp on for the dyno tune? If so, depending how it was stacked that may or may not be hurting you. But either way, from the research I've done, the throttle bodies most likely maxed out. I bet you'd make substantial gains towards meeting your expectations with as set of Raceline DTH throttle bodies, which would be a much better match to the build level of your engine. Based on their claims, for max output you'd probably be ready to even skip the 45mm and jump straight to the 48mm...Although I would wonder if the 45mm might be better on the street still, even if sacrificing some peak power.

Great looking build though, and congrats on sticking a fork in it! The likelihood of it taking 10 years to finish is one of the main reasons I call my build The Odyssey.

_________________-Justin

Also follow my build on blogspot, tumblr, or instagram and twitter (GarageOdyssey)

I bet you'd make substantial gains towards meeting your expectations with as set of Raceline DTH throttle bodies, which would be a much better match to the build level of your engine. Based on their claims, for max output you'd probably be ready to even skip the 45mm and jump straight to the 48mm...Although I would wonder if the 45mm might be better on the street still, even if sacrificing some peak power.

I was anticipating the itbs being too small but I was an optimist and went ahead any how. Now I know. I'm looking at these guys for a possible replacement for the suzuki itbs https://www.efihardware.com/products/19 ... t-50-48-45. Similar to the Raceline itbs but the itbs are tapered.

I've been watching your build for a while and I'm looking forward to your progress, hopefully it won't take as long as mine did!

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